That plan aimed to launch two private citizens (who are still unnamed) on a path similar to the one taken by NASA's Apollo 13 astronauts. It called for using the company's Falcon Heavy rocket— currently the most powerful operational launch system in the world — and its Crew Dragon capsule, which NASA astronauts are gearing up to fly for the first time in early 2019.

But SpaceX appears to be deviating from that plan. So far, it seems the company is only sending one passenger, whom Musk may have hinted is Japanese. And instead of Falcon Heavy, the company plans to use BFR.

That 35-story launch system — which is still being developed and built — is intended to eventually launch the first crewed missions to Mars. But SpaceX appears eager to demonstrate BFR's capabilities with the lunar mission.

In this new announcement, the company also seems to be rolling out a new design of the spacecraft. Musk confirmed that the rendering SpaceX shared is a new version of the BFR. He hasn't given additional details yet — more will likely come in the announcement later today — but the spaceship shown in the image (at the top of this post) appears to be more squat than the original design. It also has a large tail fin and two small wings, unlike previously shared graphics.

Business Insider will be reporting live from SpaceX's announcement, which should begin around 5:30 p.m. PT (8:30 ET) tonight.